The producers of La La Land then began giving their acceptance speeches before officials were able to correct proceedings and invite the cast and crew of the low budget film to the stage to collect their award.

Ms Boone Isaacs said the Academy’s relationship with PwC was under review.

Video:Stars react to Oscars gaffe

Prior to the mix-up, Mr Cullinan had tweeted a photo of best actress winner Emma Stone from the backstage area minutes before the best picture award was handed out.

Ms Boone Isaacs said his distraction is what caused the Academy’s worst blunder in its 89 year history.